You will have to save the "before" configuration and then use that in your undo code.
John Walkenbach has an example here...
http://spreadsheetpage.com/index.php...ba_subroutine/

Note also that the undo option should turn itself off at some point.
My Special Sort add-in undo feature, for instance, saves a sampling of cell values from the post
sort range and won't undo if those cells have changed .
--
Jim Cone
Portland, Oregon USA
http://www.contextures.com/excel-sort-addin.html
(editorial review of Special Sort add-in)





"Fede Sauret"
wrote in message
...

Thanks Jim,
yes, I did have to implement my own Undo function. But I couldn't find
a workaround to keep using the old "undo stack", neither be able to
memorize more than action to undo, since everytime the code I have is
run, the whole stack is emptied.

I know Excel empties the "undo stack" when certain things are done
from VBA. But not every time, for example if we run a HelloWorld
function as follows:


Sub HelloWorld()
MsgBox "Hello world"
End Sub

In this case undo stack will remain untouched, with all previous
actions. That's why I thought that maybe I could emulate a call to the
"fill in color" button that would not empty the stack and be
memorized.

Are you sure this is completely impossible? What about adding copies
of the default fill-in button to a custom ribbon? I could change the
icon, using a different color for each copy, and then try to run some
code that would change the picked up color before the default "fill in
button" code is run. Is this possible? How would I do it?